Method of fabricating flexible spools



OcL26, 1943. L s. FRYER ETAL METHOD OF FABRICATING FLEXIBLE SPOOLSOriginal Filed June 10. 1940 Summer: Louls SFRYER \AAYNE \LJOKILEHTOFIG. 3

attorney vent free shrinkage.

umrso s'rA'rEs PATENT. OFFICE METHOD OF FABRICATING FLEXIBLE SPOOLSLouis S. Fryer and Wayne J. Jokileh'to, Cleveland,

Ohio, assignors to Industrial Rayon Corporation, Cleveland, Ohio, acorporation of Delaware Original application June 10, 1940', Serial No.339,666. Divided and this application January 29, 1942, Serial No.428,730 r This application, which is a division of application SerialNo. 339,666, filed June 10, 1940, relates to a method of manufacturing anew type of flexible winding spool adapted for employment in theproduction, handling and treating of threadlike articles.

,-Although the spool with which the invention deals. is adapted for usein the manufacture,

- handling, or storage of anytype of thread, it is especially applicableto use in the production of multiple filament viscose artificial silkthread. In the course of its manufacture by the so-called spool-spinningsystem, such thread is customarily wound upon a rigid, perforate spoolupon which .it is successively subjected to a series of wet treatments,afterwhich it is dried. During the liquid-treating and dryingoperations, a rigid spool, even if perforated, tends to impede thethorough application of the processing fluids to the thread. It may alsobe responsible for the introduction of a variety of discrepancies intothe physical and physico-chemical characteristics of the thread. I

Such discrepancies are for the most part trace- I able to the dryingoperation, in which, by reason of the use of a rigid spool, the threadshrinks unevenly. In a typical case,. the layers of the thread packagelying nearest the spool are entirely prevented from shrinking. Theintermediate layers are .caused to shrink in different degrees since toa certain extent they are cushioned by other layers'as they are dried.The outermost layers, which dry first, are for themost part not free toshrink when they are dried. As might be expected, the resultingirregularities manifest themselves in various ways and render theproduct much less useful for certain purposes; such, for example, as inthe'weaving of cloth.

Obviously, if such processes could be adapted to produce a uniformlyshrunk thread without the necessity of repackaging, their utility wouldbe greatly increased; accordingly, the desideratum is a winding spoolwhich is sufliciently rigid to retain its shape, yet flexible enough notto interfere unduly with the shrinkage of the thread.

Many types of flexible winding spools have been developed with a view toeliminating the rigid 6 Claims. (Cl. 113-116) not displaced theconventional-rigid spool, this in 4 spite of the latters numerousdisadvantages.

The present application contemplatesa method of fabricating a novel typeof spool which 18 compressible radially when subjected to uniformpressure, yet sufflciently rigid to withstand rough treatment. In theaccompanying drawing, Figure 1 is an isometric projectionof a flexiblecorrugated spool which embodies the novel features of the presentinvention. Figure 2 represents a transverse section of the spool shownin Figure 1 obtained by passing a plane perpendicular to the axis ofsaid spool at a point intermediate the ends thereof. Figure 3 is avertical sectional elevation of the spool as seen from line 3-4 ofFigure 2.

.The spool is made from a comparatively thin gauge sheet metal in whichhave been formed a plurality of substantially parallel grooves 5 andridges 6. The number and depth of corrugations to be employed willdepend upon the diameter of the finished spool, as well as upon theintended use thereof; for example, if a highly flexible spool isdesired, it is advantageous to form therein a smaller number of groovesand ridges, but of greater depth. on the other hand, if too many or-toodeep grooves are present, especially where the normal diameter of thefinished spool is small,

interference between the grooves may unduly limit the radialcompressibility of the spool.

At both. ends of each groove 5 and ridge 6 are provided stiffening meanswhich, for the sake of convenience, are shown as taking the form ofbevels 8 and 9. They serve, among other things,

to strengthen the corrugations so that the spool as a whole readilyresists lateral warping during use. Bevels 8 and .9 further operate tofacilitate the insertion of the spool in the processing appasurfacewhich, in actual practice, operates to pre- Spools have been constructedof narrow sheet metal strips, of wire fabricated to provide a series ofaxially extending loops, in the form of so-called gapped cylinders madeof springy metal and the like, but operations with such spools have notproven successful. Among'other things, such flexible spools have ratus.'All sharp edges or burrs which tend to damage or even break the threadas it is unwound from the spool are thus removed. In addition, thepossibility of injury to the operator resulting from contact with theedges of such spools is eliminated. In forming the sheet metal to giverise to a generally tubular member, the edges of the material extendingparallel to the direction of said grooves 5 and ridges Bare joined inany convenient manner, as by a soldered, folded or welded butt or lappedconnection. 'A folded joint, such. for example, as that indicated inFigures 1 and 2 by reference character .1, is preferable inasmuch Iapproximately :the

as it does not unduly affect the static and dynamic balance of thespool. The location at any one point upon the periphery of the spool ofexcess metal which results from the employment of certain types ofjoints produces harmful effects, especially when the filled spool isrotated at high speed, as in the operation of unwinding the threadtherefrom.

Most materials after having been shaped mechanically assume a slightlydifferent shape when subjected to ordinary use for a short period oftime. After this change which the material unsheet aluminum, etc.

to size the spool may be reduced as much as possible.

in the fabrication of the spool of the present invention; for example,stainless steel, sheet iron, Obviously, the material employed mustpossess a certain degree of springiness and yet should maintain itsshape under all sorts of conditions. It must resist not only fatigue butalso the corrosive action of reagents employed in the processing ofthread.

dergoes, the article as a whole assumes a con- 'stant shape; that is, ittakes a permanent set.

By virtue of this fact, certain allowances must necessarily be made inthe course of manufacalloys possess virtually all of the more desirablecharacteristics, such as workability, lightness, and flexibility withoutearly fatigue, besides being somewhat more resistant to corrosion thanmost other-materials, they are especially adapted to use in the presentinvention.- However, deformation of this kind is particularly marked inwrought aluminum alloys, which must therefore be given especialattention.

In practice, it is desirable to employ a spool which has a constant 4 /2inch outside diameter. In a typical case, therefore,the spool is formedmechanically to an outside diameter of 5 inches from a wrought aluminumalloy sheet material of .OIO-inch thickness (Brown 8: Sharp gauge)specified according to the handbook of the Aluminum Company of Americaas alloy 52S-% H. This material has a composition of 2.5% chromium and97.25% aluminum and normal impurities, and a Brinell hardness factor of"74 (500 .kg., 10 m. m. ball).

Metal rings having an inside diameter of 3% inches are applied to'eitherend of the 5-inch The latter factor is of very great importance in themanufacture of artificial silk thread ac.- cording to a wet process, forinstance, the viscose process.

-Mat'eria1s which are readily attacked by corrosive liquids whenemployed in spin spools may, however, be treated to preventdecomposition and weakening of the spool structure. Paints and varioustypes of plastic coatings such as .hard rubber, .Bakelite, Heresite andthe like which possess a certain amount of elasticity and resistance tochipping or cracking have been found to retard the corrosive action ofthe coagulating bath upon the/spools. Accordingly, such a coating, whileoften not strictly necessary, may usually be employed to' advantage.

Modifications in the method or the character of the article may readilybe made without departting in any way from the spirit of the presentinvention. Under certain'circumstances, it may be found to beadvantageous to combine the op-v eration of setting the spool with thatof heat: treating or tempering the material. Moreover, the spool may beformed with fiat edges extending longitudinally of the ridges in placeof curved surfaces for the purpose of providing greater surface contactfor the thread turns. Many other substances than those already indicatedsuch,

of 45 hours to a constant temperature in excess of 130 F., preferablyapproximately 150 F.

After cooling or quenching, the rings are resumed permanent set.

Other wrought aluminum alloys have been found to display propertiessimilar to those of the alloy referred to in the foregoing example,fvarying principallyzin the degree of shrinka e which results from thesetting operation. Such alloys are,'for example, those designated. inthe handbook of the Aluminum Gompany of America as 51S-T, 53S-T'andBIS-T, all of which have same composition as IRS-FY4111. -It will beunderstood that with such xflalloys" the temperature employed in thesetting greater or less than that above dvantageously as high as prachatthe period of time required for example, as Micarta, Bakelite and othersynthetic plastics may be employed in the fabrication of the spool.

The structure of the spool per se is not being claimed in thisapplication but represents the subject matter of the parent applicationSerial No. 339,666 to which reference has previously been made herein.

It is intended that the patent shall cover, by suitable expression inthe appended claims, what ever features of patentable novelty reside inthe invention.

What is claimed is:

1. The method of fabricating a flexible corrugated spin spoolcharacterized by its ability to be radially compressed and to resume itsnormal shape in spite of innumerable fiexings comprising the steps offorming. a plurality of parallel corrugations in a flexible sheetmaterial, joining the edges of said sheet material extendingsubstantially parallel to said corrugations so as to fashion a generallytubular member having a diameter larger than the normal diameter desiredfor the finished spool, compressing said tubular member to apredetermined minimum diameter which issmaller than the desired normaldiameter of the 'finished spool, while ,maintaining said tubular memberin compression,

subjecting it to heat treatment to set'the tubular A wide variety ofother materials may be used smaller than the desired normal diameter ofthe finished spool, while maintaining said tubular member incompression, subjecting it toheat treatment to set the tubular member,removing the compression from the tubular member so that it will expandto the above-mentioned esired normal diameter, and cooling the tubarmember.

3. The method of fabricating a flexible corrugated spin spoolcharacterized by its ability to be radially compressed and to resume itsnormal shape in spite of innumerable flexings comprising the steps offorming in a flexible sheet material a plurality of parallelcorrugations,- joining the edges of said sheet material extendingsubstantially parallelto said corrugations so as to fashion a generallytubular member having a diameter larger than the normal diameter desiredfor the finished spool, compressing said tubular member to apredetermined minimum diameter which is smaller than the desired normaldiameter of the finished spool, while maintaining said tubular member incompression, subjecting it to heat treatment to set the tubular member,quenching the tubular member, and thereafter removing the compressionfrom said tubular member so that it will expand to the above-mentioneddesired normal diameter. 1 4. In the fabrication of a flexible spoolfroma generally tubular member the periphery of .which is characterizedby a plurality of parallel corrugations and has a diameter larger thanthe normal diameter desired for the completed spool,

the method of treating said tubular member to render it upon completioncapable of resuming its normal diameter in spite of innumerable flexingscomprising the steps of compressing said tubular member to a diametersmaller than the desired normal diameter oi the completed spool,

while maintaining said tubular member in com- 'pression, subjecting itto heat treatment to set the tubular member, cooling the tubular memher,and thereafter removing the compression from said tubular member so thatit will expand to the above-mentioned desired normal diameter.

5. The method of fabricating a flexible corrugated spin spoolcharacterized by its ability to be radially compressed and to resume itsnormal shape in spite of innumerable flexings comprising the steps offorming a plurality of parallel corrugations in a sheet metal blank,Joining the edges of said blank extending substantially parallel to thecorrugations so as to fashion a generally tubular member having adiameter larger than the normal diameter desired for the finished spool,compressing said tubular member to a predetermined minimum diameterwhich is smaller than the desired normal diameter of the finished spool,while maintaining said tubular member in. compression subjecting it toheat treatment to set the tubular 'member, cooling the tubular memberand thereafter removing the compression therefrom so that it will expandto the above-mentioned normal diameter.

6. The method of fabricating a flexible corrugated spin spoolcharacterized by its ability to be radially compressed and to resume itsnormal shape in spite of innumerable flexings comprising the steps offorming a plurality of parallel corrugations in a sheet metal blank,chamfering the ends of said corrugations, joining the edges of saidblank extending substantially parallel to the corrugations so as tofashion agenerally tubular member having a diameter larger than thenormal diameter desired for the finished spool,

compressing said tubular member to a predeter-' mined minimum diameterwhich is smaller than the desired normal diameter of the finished spool,while maintaining said tubular member in compression subjecting it toheat treatment at a temperature in excess of F. to temper the tubularmember, cooling the tubular member and thereafter removing thecompression therefrom so that it will expand to the above-mentionednormal diameter.

LOUIS S. FRYER.

WAYNE J; JQKILEEI'Q.

